Anvil for a chain rivet removing device



May 29, 1956 J. B. cox

ANVIL FOR A CHAIN RIVET REMOVING DEVICE Filed Sept. 18, 1951 1 N VEN TOR.

14 EYQMMW Ea. AWnW/EVS United States Patent ANVIL FOR A CHAIN RIVET REMOVING DEVICE Joseph B. Cox, Portland, Oreg., assignor, by mesne assignments, to Oregon Saw Chain Corp., a corporation of Oregon Application September 18, 1951, Serial No. 247,048

1 Claim. (Cl. 59-7) This invention relates to a rivet remover and more particularly to a punch press for effecting the removal. of rivets from chains such as saw chains and the like.

In one type of saw chain construction the chains include a plurality of centrally disposed links pivotally joined together by pairs of oppositely disposed side plates. The rivets joining the side plates to the central links are provided with a central enlarged annular shoulder which is cooperatively received by the central link. The extending end portions of the rivets upon which the side plates are engaged are of considerably smaller diameter than the annular shoulder and the opening in the side plate which receives the extending portion of the rivet is also of lesser diameter than the annular shoulder. This enlarged annular shoulder makes it impossible to simply punch out a rivet as is done with various assemblies having a rivet of the same diameter throughout.

Since the rivets can not be punched out, the conventional practice of the users of this type of chain has been to hold the saw chain in a machinists vise and with a hand hammer and chisel cut and pry the chain apart. This method of disassembly is not only difficult to perform, but invariably the various parts of the chain are so damaged that they cannot be used again.

It is an object of this invention to provide a device adapted for removal of rivets from chains wherein the removal entails a plurality of punching steps with the chain securely held in various positions.

It is another object of this invention, therefore, to provide a means for disassembling a saw chain without injury to the component parts thereof.

It is a further object of this invention to provide a device adapted for disassembling saw chains of more than one size.

It is another object of this invention to provide means for quickly and easily disassembling a saw chain.

It is a still further object of this invention to provide a simple, efficient and durable means for disassembling saw chains which is inexpensive to manufacture.

According to the embodiments herein shown, there is provided in the present invention a rivet remover having a vertically disposed head with a vertically movable punch disposed therein. Supported upon a base below the punch is a movable anvil having surfaces adapted to support a chain and its component parts while the rivets are punched out without injury to the parts.

The foregoing and other objects and advantages of the present invention will be more readily ascertained from inspection of the following specification taken in connection with the accompanying drawing wherein like numerals refer to like parts throughout, while the features of novelty will be more distinctly pointed out in the appended claim.

In the drawings:

Fig. 1 is an elevational view of the rivet remover of the present invention partly in cross section showing the first step in disassembling a saw chain;

Fig. 2 is a front elevation of the rivet remover;

Fig. 3 is a perspective view of the movable anvil;

Fig. 4 is a side elevation partly in cross section showing the second step of disassembling a saw chain;

Fig. 5 is a side elevation of a saw chain of the type with which the rivet remover is especially adapted; and

Fig. 6 is a sectional detail taken substantially on the line 6-6 of Fig. 5.

The rivet remover of the present invention is particularly adapted for use with saw chains having the characteristics of those illustrated in Fig. 5 and Fig. 6. Referring now to those figures, there is shown therein a saw chain consisting of a plurality of centrally disposed links 10 having sprocket engaging root portions 11 depending from the lower edge thereof. It will be understood that the root portions 11 of the saw links 10 ride within the groove 13 of the saw bar indicated generally at 14 in Fig. 6. The links 10 are pivotally joined together by means of pairs of oppositely disposed side plates 18 and 19. The side plates 18 are identical with each other whereas the side plate 19 has a hook-shaped tooth 20 formed on the upper end thereof and is provided with a depth gauge 21 ahead of the tooth. The conformation of side plate 19 is of no great concern to the present invention and for further details thereof reference is made to my Patent No. 2,508,784, issued May 23, 1950.

Referring now to the enlarged view of Fig. 6, the central link and side plate elements are pivotally connected together by means of rivets 25, the central portion of the rivets being provided with an enlarged annular shoulder 26 having a width very slightly greater than the thickness of the central link member 10 and a diameter slightly less than the cooperating opening provided there in so that the link member 10 may pivot freely thereabout. The side plate members are provided with openings 27 for cooperatively receiving the opposite ends of the rivets 25. To secure the link elements together the rivets 25 are spun or peened over the side plates as shown whereby the opposite side plates are permanently fixed against the shoulders provided by the rivet portion 26. As best shown in Fig. 5, the longitudinal edges of side plates 18 are substantially straight and parallel and the central links 10 have a portion 22 extending beyond one edge of a plate and a portion 23 extending beyond the other edge of a plate along a line at right angles to the edges passing through a rivet 25.

Turning now to the invention of this application, the illustrated embodiments illustrate a rivet remover including a frame 29 which may be conveniently cast having a base portion 30 and a head portion 31 spaced above the base. A feed screw 32 is carried by the head in a threaded ferrule 33 which is preferably pressfitted into the head 31. Carried by the feed screw 32 is a hardened, detachable punch 34 secured to the feed screw by a locking nut 35. As is obvious, by reason of the above construction, the various parts are adapted for easy replacement in case of wear.

Complete disassembly of a rivet from a chain requires two distinct operations which are facilitated in the present invention by a movable anvil block 45 adapted to be changed in its position to assist in these distinct operations. As shown in Fig. 3, the movable anvil block 45 is generally rectangular, having longitudinal grooves or recesses 46 and 47 defined in opposite faces thereof between parallel shoulders 52. Preferably, to increase the versatility of the rivet remover, the width of one of the grooves is made to admit a side plate 18 of one size of chain aligned longitudinally therewith in a close-fitting but non-binding relation, with the other groove adapted to admit a side plate of a chain of another size chain in the same manner. Obviously, a block can be formed with one groove, or with two grooves of the same width and with other configurations which will be apparent from an understanding of the invention. For convenience in indicating a particular groove, for example, the one of narrowest width, the edges 48 of the anvil paralleling the groove may be beveled as shown in Fig. 3. The grooves are preferably formed with a depth at least equal to the thickness of a side plate plus the height of the peened over portion of a rivet. At least one other face of the block, and preferably the pair of oppositely disposed faces paralleling the faces carrying grooves 46 and 47, is provided with a circular opening or recess 5% of a diameter just slightly larger than the annular shoulder 26 of rivet 25. Preferably, the opening 50 is provided by means of a hole through the block to facilitate removal of punched out rivets through hole 41 in the base portion 30 aligned therewith.

To accurately center the anvil below the punch, "loans are provided on the base cooperating with means on the anvil to hold the anvil centered. One form of centering means is illustrated which includes a pair of laterally spaced pins 40 projecting upwardly from base 30 and spaced equally on opposite sides of the axis of the punch 34. To hold the anvil with groove 46 properly aligned below the punch, a pair of holes 49 are bored entirely through the block along the center line of the groove, the holes being spaced and of such diameter as to cooperatively receive pins 40 therein when the anvil is centered on the base 30 below the punch as shown in Figs. 1 and 2. Likewise the side of the block opposite the side containing opening 50 has holes 51 bored therein to cooperatively receive pins 40 and hold opening 50 centered beneath punch 34 when the anvil is placed in the position illustrated in Fig. 4. The block is conveniently prepared by boring opening 5t) and holes 51 entirely therethrough as illustrated.

Referring again to Fig. l, a rivet is removed from a saw chain with the rivet remover of the present invention by first placing the anvil 45 on base portion 30 with a groove of desired width facing upwardly, the block illustrated having groove 4-6 facing upwardly. The saw chain is then placed on the anvil with one of the side plates 13 inserted in the groove and with the extending portions 22 and 23 of central link resting on the shoulders 52 of the anvil block and with a rivet 2.5 centered directly below punch 34. The feed screw 32 is then turned so as to lower punch 34 which, as shown, forces rivet 25 out of the upper side plate 18 shearing off the spun over edges of the rivet from the central portion. The lower side plate 18 is engaged by the shoulders of the enlarged annular portion 26 of rivet 25 and consequently is forced downwardly into the groove 46. Preferably the feed screw is turned until punch 34 forces the rivet 25 entirely out of the upper side plate i8. After performing the above operation on both pins securing a pair of side plates and a pair of links 10 together, both of the side plates are freed from the chain but one of them still carries therein the rivets 25. The next step is to remove the rivets 25 from this latter side plate. To accomplish this, the anvil is turned 90 by lifting it upwardly with the fingers to disengage the pins 40 from holes 49 and replacing it with holes 51 engaged on pins 43 and with opening 50 aligned with punch 34. The side plate carrying the rivets 25 is then positioned on the anvil with the enlarged annular portion 26 of one the rivets 25 within the hole 50 and the punch is turned down to punch out the rivet as shown in Fig. 4. The operation is then repeated to remove the remaining rivet. As is apparent these operations just described enable removal of the rivets with no injury to the links or the side plates of the saw chain.

The rivet removed of this invention may be supplied with a number of anvils dimensioned to fit chains of various sizes. Also the punch 34 can easily be interchanged with punches of varying sizes to meet varioussized rivets which may be encountered in different types of saw chains and its design is such that it may be manufactured economically and the parts subject to wear may easily be replaced.

The interchangeable anvil principle of this invention can obviously be applied to punch presses for removing rivets from chain structures other than saw chains. For example, a piece of heavy mechanical equipment frequently employs chains of several sizes in the various drive mechanisms. Thus a convenient tool for use in repairing these chains is a single punch press structure supplied with a plurality of anvils each adapted to hold one of the chains with the base of the press and the anvils cooperatively arranged whereby a particular anvil will be held on the base with a chain carried thereby in the proper position below the punch.

Having illustrated and described a preferred embodiment of the invention, it should be apparent to those skilled in the art that the invention permits of modification in arrangement and detail. I claim as my invention all such modifications as come within the true spirit and scope of the appended claim.

I claim:

A rivet remover adapted for use with saw chains of the type having longitudinally spaced-apart, centrally disposed links pivotally joined to pairs of oppositely disposed side plates by means of rivets provided with a central enlarged annular shoulder cooperatively received by said links, each of the extending end portions of said rivets being cooperatively received by an opening in a side plate of lesser diameter than said shoulder, said rivets being peened over said side plates at the extreme ends thereof so as to hold said side plates in position, the longitudinal edges of said side plates being substantially straight and parallel, said centrally disposed link extending beyond said edges, said rivet remover comprising a frame including a horizontally disposed base portion and a head portion spaced above said base portion, a punch mounted on said head portion for movement toward and away from said base portion, an anvil block, said anvil block comprising a pair of upwardly projecting parallel shoulders defining a groove open at both ends, said groove having a width substantially equal to the distance between the longitudinal edges of the side plates of a saw chain of predetermined size whereby the anvil will support such a chain beneath said punch with a side plate of the chain disposed between said anvil shoulders and with the said extending portions of the centrally disposed links resting on said anvil shoulders, said groove being of a depth at least as great as the thickness of a said side plate plus the heighth of a peened ever end portion of a said rivet and the axial length of the rivet shoulder, said anvil having a transverse circular aperture of a diameter slightly greater than the diameter of said rivet shoulder, and cooperative mounting means on said anvil block and on said base for centering said groove beneath said punch with the longitudinal direction of said groove extending transversely of the frame between said base and head portions and for centering said aperture beneath said punch.

References Cited in the file of this patent UNITED STATES PATENTS 560,443 Stanton May 19. 1896 1,208,092 Carter Dec. 12, 1916 1,436,429 Bean Nov. 21, 1922 1,445,326 Krebs Feb. 13, 1923 2,361,971 Shipman Nov. 7, 1944 2,509,932 Leeth May 30, 1950 FOREIGN PATENTS 41,802 Switzerland Dec. 16, 1907 

